This seems like your language settings might be set incorrectly. Possibly Western Frisian? Check the keyboard settings to be sure though.
No, that is not the issue. It's set to English. Anything I mistyped gets added to the dictionary and suggested as a spelling correction.
How strange. Both those words are actual words in Western Frisian lol. It is possible there is an alternate language enabled on the phone itself? Does this happen if you use Gboard too, or is this problem only occuring with the Samsung Keyboard?